HSP Diesel

HSP Turbo Inlet Horn for Stock or Drop in LB7 Turbos

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  • Regular price $161.50
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This product may have a lead time, please confirm with sales@dieselpartdeals.com if in a rush

The 103-HSP or better known as the HSP Stock Turbo Inlet Horn for the 2001-2004 Duramax Equipped Chevrolet and GMC Trucks is one of those parts that for the LB7 you should not forget. The HSP Stock Turbo Inlet Horn is leaps and bounds better than the factory.

Why would you need an HSP Stock Turbo Inlet Horn for the 2001-2004 Trucks?

The stock turbo inlet horn on the LB7 trucks is not great by any means. Now there are a few reasons why HSP Diesel thinks this and many others. Let’s start with the performance of the factory turbo inlet horn, the turbo inlet horn’s job is to funnel air from the intake into the turbo. The factory piece does not do a good job, it is very restrictive and does not flow well due to size and its bends. The stock turbo inlet horn also is very plain looking, it really doesn’t accent anything and can not really be cleaned up.

What does the HSP Stock Turbo Inlet Horn for the 2001-2004 Trucks do Differently?

To start the HSP Stock Turbo Inlet Horn is a massive 3.5 inches. This is so much larger than the factory piece. The reason we wanted it bigger was that with a larger diameter turbo inlet horn you are able to flow more. The biggest complaint with the LB7 trucks is that the stock turbo just feels choked. The factory IHI turbo needs to be able to consume as much air as possible no matter the circumstances. With the small addition of the HSP Stock Turbo Inlet Horn, you can jam-pack that stock turbo with so much more air than the factory that you will be able to push the stock turbo much farther. With the HSP Stock Turbo Inlet Horn, many customers reported power gains with no other changes. When the HSP Stock Turbo Inlet Horn is combined with the HSP Diesel Cold Air Intake we saw a slight drop in exhaust gas temperatures.

What comes with the HSP Stock Turbo Inlet Horn for the LB7?

  • Turbo Inlet Horn
  • (3) M6x1.02x20mm

What Does the HSP Stock Turbo Inlet Horn for the LB7 Fit?

  • LB7: 01-04 VIN Code 1

How do people know the VIN code?

Engine code is dictated by the 8th character of the VIN number. The 10th character is the year of the truck.

*Special Note*

Only install with bolts supplied. Do NOT attempt to install with factory hardware


  • Designed as a direct replacement for stock applications
  • More airflow
  • Increased power
  • Powder Coating available to clean up the engine bay
  • Extended turbo life
  • Quicker turbo spool up

Our Warranty


At HSP we believe in our products and we stand firmly behind every single one that leaves our facility. For years we have taken care of almost everything & anything that our customers had issues with, but we didn’t have a “set in stone” warranty. We have always gone above and beyond for our customers which set us apart from the rest. We will continue that same standard, but now we are taking things to the next level. Below you will be able to clearly read & understand our “No BS” warranty, its process, and the guidelines in which to follow.